If you have a good sidewinder with everything working stick with it.
There is no real improvement to be had stick wise from what I've seen.
Plus the sidewinders tended to be very durable, no pots to go bad.
Pinched cords seem to be the biggest cause of failure I've seen.
If you search back in this forum you'll find threads with links to replacement switch's, etc.
Good sidewinders are also still available on Ebay, but you need to read them carefully. There are a lot of the old 3d pros, and precision pro's out there.
Price vary's a lot but if you take your time, and are choosy you can get them for around 30$.